Rockwell Automation 1797-Series ControlNet Ex Media Plannng Installation Manual - Manual (Page 67)

Publication CNET-IN003A-EN-P - January 2006
Install a ControlNet Ex Media System 3-25
3. At the same end of the cable tested in step 1, use an ohmmeter
or continuity tester to test for electrical continuity.
Connect Cable Sections Connect the cable sections to the tap’s BNC connectors and cover all
exposed metal with intrinsically-safe insulators.
Terminate Segments The taps on the ends of the segment have only one cable connector
attached to them. This leaves an open, or unterminated, end on the
segment. Signals transmitted along the cable will reflect off these
unterminated ends and interfere with transmission.
To eliminate signal reflections from the ends of the segment, you must
attach a 75
Ω
trunk terminator (catalog number 1797-XT) to the first
and last taps on the segment. The terms first and last refer to the
physical location of the node along the trunk cable.
If Resistance Reading Indicates Then
That a short exists Continue to next section.
There is no short Use your wire cutters to cut off the
connector, install a new connector,
and begin testing again.
31195-M
LENGTH
WIRE MAP TEST
SETUP ENTER
OFF
MediaChecker
1788-MCHKR
Attach the connector end of the
cable to the port on top of the
media checker.